Study of Globular Cluster M53: new variables, distance, metallicity (2009)
We study the variable star content of the globular cluster M53 to compute the physical parameters of the constituting stars and the distance of the cluster. Covering two adjacent seasons in 2007 and...
Current status of (the lack of) understanding Blazhko effect is reviewed. We focus mostly on the various components of the failure of the models and touch upon the observational issues only at a...
HAT-P-13b,c: a transiting hot Jupiter with a massive outer companion on an eccentric orbit (2009)
Bakos, G. A., Howard, A. W., Noyes, R. W., Hartman, J., Torres, G., Kovacs, Geza, ...
We report on the discovery of a planetary system with a close-in transiting hot Jupiter on a near circular orbit and a massive outer planet on a highly eccentric orbit. The inner planet, HAT-P-13b,...
HAT-P-10b: A light and moderately hot Jupiter transiting a K dwarf (2008)
Bakos, G. A., Pal, A., Torres, G., Sipocz, B., Latham, D. W., Noyes, R. W., ...
We report on the discovery of HAT-P-10b, the lowest mass (0.46 +/- 0.03 MJ) transiting extrasolar planet (TEP) discovered to date by transit searches. HAT-P-10b orbits the moderately bright V=11.89 K...
HAT-P-9b: A Low Density Planet Transiting a Moderately Faint F star (2008)
Shporer, Avi, Bakos, Gaspar A., Bouchy, Francois, Pont, Frederic, Kovacs, Geza, Latham, Dave W., ...
We report the discovery of a planet transiting a moderately faint (V=12.3 mag) late F star, with an orbital period of 3.92289 +/- 0.00004 days. From the transit light curve and radial velocity...
HAT-P-7b: An Extremely Hot Massive Planet Transiting a Bright Star in the Kepler Field (2008)
Pal, A., Bakos, G. A., Torres, G., Noyes, R. W., Latham, D. W., Kovacs, Geza, ...
We report on the latest discovery of the HATNet project; a very hot giant planet orbiting a bright (V = 10.5) star with a small semi-major axis of a = 0.0377 +/- 0.0005 AU. Ephemeris for the system...
On the Cepheid Metallicity Dichotomy (2008)
With the aid of stellar atmosphere models, we derive iron abundances [Fe/H] from the OGLE B, V, I photometry on the Magellanic Cloud Cepheids. We show that in both clouds the average metallicities of...
HAT-P-6b: A Hot Jupiter transiting a bright F star (2007)
Noyes, R. W., Bakos, G. A., Torres, G., Pal, A., Kovacs, Geza, Latham, D. W., ...
In the ongoing HATNet survey we have detected a giant planet, with radius 1.33 +/- 0.06 RJup and mass 1.06 +/- 0.12 MJup, transiting the bright (V = 10.5) star GSC 03239-00992. The planet is in a...
HAT-P-5b: A Jupiter-like hot Jupiter Transiting a Bright Star (2007)
Bakos, G. A., Shporer, A., Pal, A., Torres, G., Kovacs, Geza, Latham, D. W., ...
We report the discovery of a planet transiting a moderately bright (V = 12.00) G star, with an orbital period of 2.788491 +/-0.000025 days. From the transit light curve we determine that the radius...
Searching for Variables in One of the WHAT Fields (2006)
Shporer, Avi, Mazeh, Tsevi, Moran, Amit, Bakos, Gaspar, Kovacs, Geza
We present preliminary results on a single field observed by WHAT, a small-aperture short focal length automated telescope with an 8.2 deg x 8.2 deg field of view, located at the Wise Observatory....
On the incidence rate of first overtone Blazhko stars in the Large Magellanic Cloud (2006)
By using the full span of multicolor data on a representative sample of first overtone RR Lyrae stars in the Large Magellanic Cloud (LMC) we revisit the problem of the incidence rate of the...
Metallicity effects on distances based on double-mode Cepheids (2005)
We test the effect of systematic metallicity difference between the two types of double-mode Cepheids in the Magellanic Clouds. We show that lowering the metallicity for the short-periodic Cepheids...
Iron abundances derived from RR Lyrae light curves and low-dispersion spectroscopy (2005)
With the aid of the All Sky Automated Survey (ASAS) database on the Galactic field, we compare the iron abundances of fundamental mode RR Lyrae stars derived from the Fourier parameters with those...
On the Light Curve - Luminosity Relation of RR Lyrae Stars (1996)
Kovacs, Geza, Jurcsik, Johanna
We use a large sample of RRab stars in globular clusters and in the Sculptor dwarf galaxy to decipher the relation between the Fourier decomposition and the luminosity. For fixing the zero point of...